Electrical switch



Bea 27, 192?. 1,653,941

a. A. BROWN ELECTRICAL SWETCH Filed Watch 8, 1926 9:; 0i 0 0 0'0 u.s.GALLONS INVENTOR,

ATTOR Y r Patented Dec. 27,

CHARLES ARTHUR BROWN, OF LORAIN, OHIO.

ELECTRICAL swiron.

Application filed March 8, 1926. Serial 110. 93,031.

My invention relates to electrical switches and relates moreparticularly to those types of electrical switches wherein it is desiredto operate a set of electrical contacts quickly, so that sparking at thecontacts will be reduced.

An object of my invention is to accomplish the breaking of an electricalcircuit quickly to prevent the undue arcing at the contacts, which wouldotherwise occur where the contact elements separated more slowly.

Another object of my invention is to accomplish a closure of anelectrical circuit by the continued application of effort of low torquevalue tending to'close the contacts.

Another object of my invention is to accomplish a momentary closure ofan electrical circuit which will be positive, though of short duration,and in which the malrng and breaking of the contacts effecting theclosure will positively and quickly accomplished.

Another object of my invention is to produce an electrical contactmechanism which will be capable of being ef iciently operative byindicating apparatus with a minimum of effort,and in which the movementseffecting the closure of the contacts may be effected at a very slowrate, but in which mechanism, nevertheless, the movement of the parts atthe contact operating period will be rapid.

, Other objects of my invention and the invention itself will beapparent from the following description of an embodiment of myinvention, in which description, reference will be had to theaccompanying drawings forming a partof this specification, and in whichdrawings is illustrated an embodimentof my invention as applied to aliquid meter mechanism, for the purpose of closing an electrical circuitat certain points in the operation of the meter mechanism when itrecords a predetermined amount of liquid flow.

Referring to the drawings:

Fig. 1 shows a plan view of the said embodiment of my invention;

Fig. 2 shows an elevational view of the said embodiment;

Fig. 3 shows a side elevational View of an insulating cam elementcomprised in the said embodiment;

Fig, 4-, is a plan view of the said cam ele ment;

Fig.5 isan enlarged view in section, of a portion of the sa1d 1nsulat1ngcam and electrical contact provided in a face thereof,

together with a portion of the mount 11g I therefor, and electricalconnection means associated therewith; and f Fig. 6 is a view of theelectrical cont-act element with an integral stem of Fig. 5.

Referring now to all of the figures of drawing, in all of which likeparts are designated by l ke reference characters, at l, I show a faceplate and at'2 .a back plate, of a recorder ofv liquid flows, the saidplates being suitably joined together by spacing rods 3, whichpreferably have reducediends,

such as l, riveted over at their heads to retain the plates on the saidreduced ends. At 5, I show adriving rod, herein shown as broken off at46., but whichwould be joined at a portion beyond the point 46 to adriving element of a liquidfiow meter so that rotative movements of therod 5 will be connnensurahle at all times with the amount of liquid flowpassing the meter.

Ati', 8, 9, l and 11, I show a train of gear pinions adapted to drivethe pinion 11 from the rod to operate the odometer shown generally at12. The odometer and its driving connections are no part of the presentinvention and will not be described in detail. The odometer portion,however, is secured by its face plate 13 to the back plate 2 andpresents its numeral carrying disks to view through an opening 14: inthe face plate 1 of the mechanism. The rod 5 has a reduced end 15projected through an opening in the face plate 1 and rigidly securedthereto. Adjacent the end of the reduced portion of the rod 5, I affix apointer hand 6 having a scale division pointer arm 16 and a rearwardlyextending electrical contact arm 17. Secured to the front of the faceplatel. by machine screws 39, and t1, I provide an insulating camelement 19, the said insulating cam element having a recessed faceZOdisposed within an outer raised cam face 21 of annular form and whoseouter, surface is in the form of a helix. i i

In that portion of the description following, relating tothe insulatingcam element 19, the contact arm 6 and associated parts, the descriptionwill be given, using the terms upper-and lower, up and down and thelike, under the assumption that the mechanism is placed in a positionwherein the face plate 1 is horizontal. Vith this in mind, the uppersurface of the insulating element ll) is in the form of a helix, thehelix having,- its lowermost portion at and its most elevated portion at21. Intermediate the por tious 22 and 21,, it provide a step surfacewhich is elevated relative to the surface porlion of the insulatinv'element and prefer ably equally depressed from the surface portion Lilthereof. The step '18 is preferably faced at 23, shown, with an end ofan electrical contact element and having its body portion embedded inthe insi'ilating nuiterialof the element 19 and having an integrallyjoined stem 24; projecting therefrom through theface plate 1 butinsulated tl'ierefrom by a bushing; 26 and an outer ming 2T concentrictherewith, the contact :1 hemp secured in its place L means of aclamping nut J8 screw threaded upon the threaded eudfii) of the stem 2%.The infilllitiiP-Q portions of the. step 18, disposed laterally of thecontact 233, have their surface prcferabl y depressed slightly from thesurf cc of the contact 23. Art- 30, I cut away an end portion. of theannular helix of greatest height to permit the proper placement of thecontact 23, a portion of the contact 23 being disposed between the forksof this portion of the insulated helix. Art :25, I provide a depressedcontact portion for the arm 17 of the indicator hand 6 and whichportion, at all times, is spring pressed by the power of the inherentresiliency of the metallic springmaterial, of which the hand 6 ispreferably made, against the upper helical surface of the insulatingelement 19. This accomplished by giving the hand (3 a normal formwherein the contact end 25 would be deflected downwardly to a. greaterextent than is the case when, secured upon the reduced end of the rod 5,it bears upon the upper blllftJCC of theiusulating element 19.

In Fig. l is shown one of the rotative posh tions of the indicator handrelative to the scale 31, affixed to the faceplate 1 extraperipherallyof the annular insulating element 19 and. relative to the contact 23. Inthis position no electrical contact would he lied between the contactportion 25 of the hand and the contact 23. The direction of rotation ofthe hand is herein assumed to be that indicated by the arrow 32.However, when the hand is rotated. by the mechanism driving the rod toan indicating position, where it points to a point just in advance ofthe point marked 0, the contact portion will have moved upwardly, beingpropelled on the upwardly ascending helical surface to a point indicatedby dotted lines in Fig. 1, riding upon, at the time, the most elevated.portion 21 of the'helical surface of insulating material. v

Although the position of the contact porma .25 is above thatportimi ofthe Conta t 23, which lies between the forks of the annular track, whichis designated by the reference numeral 33, no electrical contact is badtherewith, since the contact portion will be maintained elevated byresting upon the elevated fork portions.

New, assuming a continued movement of the point or hand in a clockwisedirection, indicated by the arrow, the contact portion thereof will. bebrought to the brink of the precipice formed by the edge of the elevatedportion of the helix, and by the inherent resiliency of the arm 17 ofthe hand. it will snap downwardly, making a quick, positive contact with the contact element Likewise, being; brought to the brink of thesecond precipice fornmd by the edge of the step 18, which comprises thecontact 25, a second. rapid spring pressed descent will be efi'ecled tocause the contact portion of the hand (i to snap to its lowerulostposition, wherein it will, rest upon the surface iudi rated at 22 of theannular insulating cam element. Continued rotation of the hand will.gradually raise the portion 25, moving it along the helical surface asbefore de scribed and with the above operation. repeated.

l [ind that by varying the length of the step 18, l: may prolong theperiod of contact had between the hand (-3 and the contact 22' or, asillustrated, by making this very short I secure but n'ion'ientarycontact between, these elen'ients, the contact home made and thenimmediately broken, botn actions being simultaneous, extremely rapid andwithout involving any undesirable degree of sparking at the contactsupon the making or breaking of the circuit, even though circuitconductors 34 and 35 are con nectcd to the. frame of the mechanism, andtherel'iy to the hand. (i and to the electrical contact 323,respectively, by a suitable electrical connecting post shown at 36 forthe conductor, and by a machine nut 37 adapted to clamp the circuitconductor 34. to the threaded end 29 of the stem Jelfor the contactI-laving described my invention in a specific embodiment. I am awarethat. the same is capable of being embodied in structures varying inwidth from that herein illustrated and described but comprised withinthe scope of my invention, being of the spirit thereof.

hat I claim is:

1. In an electrical switching mechanism. the combination with arotatable driving ele ment for the switch, a resilient metallic bladesecured thereto, an element of insulating material having an outer camsurface upon which a portion of the said blade is pressed and rideswhenever rotative move meats are imparted to the blade, said blade exertng a cons ant spring pressure upon th said cam surfaceand beingrotatable in a direction whereby its contacting portion is elevated toincrease such spring pressure, said cam surface having its most elevatedand most depressed portion joined bva step surface intermediate thereof,an electric contact element con'iprisinn' a portion of the said step,said most elevated portion having a precipice edge adjacent the step,said step having a precipice edge adjacent the said most depressed camportion, a contactportion of the said blade, upon rotative movc-,

in a direction whereby its contacting portion is elevated to increasesuch spring; pressure. the opposite end of the blade is provided with apointer projecting beyond the cam surface over a scale disposedextraperipherally thereof, the most depressed and most elevated portionsof the cam surface being disposed closely adjacent, an electricalcontact element comprising a portion of the said step, said mostelevated portion having a precipice edge adjacent the step, said stephaving a precipice edge adjacent the said most depressed cam portion, acontact portion of the said blade, upon rotative movements in'ipartedthereto, adapted to snap over the precipices consecutively.

In an electrical switch, the combination of a rotatable arm with twoends, one 0% which constitutes a hand to indicate the traction or wholeof a revolution of said hand, the other constituting a. springelectrical terminal in contact with and revolving over an insulating;element, said insulating element having, at a point in its periphery, ashort inclined plane rising above the mean level of the, insulatingelement, up which the spring electrical terminal must travel and fromwhich it must snap instantaneously oli' onto a short horizontal plane inwhich is embedded a second electrical contact and across which secondelectrical terminal the traveling spring electrical terminal must brushafter such instantaneous contact has been made, thus keeping bothterminals clean, the traveling spring electrical contact then snappingoil instantaneously from the imbedded terminal onto a lower inclinedplane in the insulating element, from which it travels back up to themean level of the insulating element, thus making and breakingelectrical contact instantaneously, keeping both terminals clean andpreventing electrical arcing between terminals.

In testimony whereof I hereunto aliix my signature this 1stday of March,1926.

CHARLES ARTHUR BROVJN.

